Food Demand & Climate Change

Have you noticed the food headlines (e.g. here and here) of late? A new study published by engineers, plant scientists, and food specialists from the Universities of Cambridge and Aberdeen used a transparent, data-driven model to demonstrate that projected food demand will drive agricultural expansion, contributing to critical environmental issues such as the loss of biodiversity, climate change and pollution. The authors, Bajželj et al. (2014), warn that it is absolutely essential to find ways to achieve food security without promoting the negative side effects of agricultural expansion and increased greenhouse gas (GHG) emissions.

Cattle livestock. Source: The Guardian (2014)

Bajželj et al. (2014)'s study aimed to estimate the environmental implications of the projected increase in food demand by 2050. They were also interested in quantifying the extent to which measures including sustainable intensification and demand reduction could reverse these negative effects. The authors' approach was to use a model of the current global land system based on emprical data, with 2009 as a base year. The model included 2 main components, namely an analysis of land distribution leading to the allocation of land-use change, natural ecosystem losses, and GHG emissions, and a map of agricultural biomass flows. Based on their analyses, the authors concluded that an increased demand for inefficient pathways of food supply such as livestock products causes the food production system to become larger and increasingly inefficient. 

The authors then went on to investigate 6 future scenarios based on agricultural intensification, waste reduction and dietary preferences. Their results indicated that increases in agricultural expansion and agriculture-related GHG emissions were only prevented when significant elements of demand reduction were included. Bajželj et al. (2014) suggest the reduction of meat consumption and an overall improvement of diet as potential solutions to avoid reaching dangerous levels of climate change.

We touched on meat consumption in previous posts (e.g. here and here), and saw that demand for animal products has been increasing in recent decades. Based on the evidence presented in scientific studies such as the one described above, would you be willing to decrease your intake of livestock products to take action on climate change? I, for one, am certainly convinced!

I'd love to hear your thoughts on meat consumption and climate change, or any aspect of the food production system at all. Feel free to share in the comments section below. 

What's wrong with our food system?

The other day I came across this particularly interesting video titled "What's wrong with our food system?" The most impressive part - it's given by an 11-year-old kid, Birke Baehr who dreams of becoming an organic farmer! He covers all sorts of issues, such as marketing of food to factory farming and pesticides. I thought the depth of his knowledge was so impressive. I can tell you that when I was 11 years old, I definitely wasn't thinking about where my food was coming from! I hope you all enjoy his talk as much as I did!

A small aside - in his video, Birke mentions that "corn is in everything". If you'd like to learn more on the subject, I strongly recommend Michael Pollan's book The Omnivore's Dilemma. Pollan (2006) follows the food chain through industrial farming, organic farming, and finally foraging. For me, it was really fascinating (and surprising) to learn about corn's colossal presence in the farming and food industry.

Thanks for reading! 

The Other Inconvenient Truth

While researching the environmental impacts of increased meat consumption, I came across an excellent TED Talk by Jonathan Foley titled The Other Inconvenient Truth. He describes the current state of the food system and identifies the need for future solutions so that we can feed 9 billion people by 2040. He covers some examples of the environmental impacts of  the modern agricultural system, including the drying of the Aral Sea and rainforest degradation in South America. His talk provides a really nice review of some of the information covered in Are Humans Becoming More Carnivorous? as well as a nice segue into some of the future topics that we'll be exploring here.

If you have twenty minutes to spare, you can check out his talk below.

If not, here's the short and compelling clip that Jonathan shows at the end of his talk.

Thanks for reading!

Are Humans Becoming More Carnivorous? Environmental Impacts

In the previous post, we examined a new study by Bonhommeau et al. (2013) which revealed that global meat consumption has increased over the past five decades. How does an increase in meat consumption affect the environment?

Cows (photo from Living Green Magazine)

The livestock sector lies within the top two or three of the most important contributors to environmental issues, both locally and globally. Despite not being a major global economic player, the livestock sector is beneficial and crucial to society, employing and feeding growing global populations (Steinfeld et al., 2006; Herrero et al., 2009). Livestock agriculture contributes to environmental problems such as land degradation, land use change, climate change and greenhouse gas emissions, water shortage and pollution, nutrient excretion, loss of biodiversity, and competition for human food (Steinfeld et al., 2006; Janzen, 2011). These environmental impacts are driven by growing stresses on global human populations, namely the those of food, water, and energy security, biogeochemical interferences, and habitat (Janzen, 2011).

Let's now examine some of these impacts in a bit more detail. Many of the other impacts mentioned above will be the topics of future posts.

Land Use Change and Degradation

Land use refers to the ways in which land is used for human means. It is "characterised by the arrangements, activities and inputs that people undertake in a certain land cover type to produce change, or maintain it" (FAO, 2013). Land degradation refers to the reduction of resources as a result of processes which act on the land, including soil erosion, deterioration of the properties of the soil, and loss of natural vegetation (Steinfeld et al., 2006).

Deforestation for agriculture in Brazil's Pantanal wetland 
(from JNCC, 2013)

Livestock now represents the largest portion of human land use forms, affecting ecosystems around the world (Janzen, 2011). An example of environmental problems brought on by land use change for agriculture is the degradation of tropical rainforests, such as the Amazon. Two main phenomena are related to deforestation as a result of intensive raising of livestock, the first being the direct conversion of forest to pasture land and the second being the clearing of forest for crop growth to feed livestock (Herrero et al., 2009). Approximately 20-30% of the Earth's land surfaces are used for grazing, while approximately one third of cultivated land area is used to feed livestock (Janzen, 2011). 

GHG Emissions & Climate Change

Climate change is possibly the most pressing environmental challenge that has faced the planet. According to the IPCC (2013), the main authority on climate change, the "warming of the climate system is unequivocal, and since the 1950s, many of the observed changes are unprecedented over decades to millennia". This warming can be seen in the atmosphere, the ocean, the cryosphere, in sea level, and in carbon and biogeochemical cycles. The largest contributor to total radiative forcing is caused by the increases in anthropogenic GHGs, such as CO2, since 1750.

Disintegrating iceberg near West Greenland
(from The Guardian)

Animal agriculture produces GHG emissions in the form of CH4 from enteric fermentation, N2O from fertiliser use, CH4 and N2O from manure management practices, and CO2 from from fossil fuel and energy use (O'Mara, 2011) and land use and its changes (Herrero et al., 2009). Livestock induced emissions account for 2.4 billion tonnes of CO2 per year, and on a life cycle analysis basis, they contribute up to 18% of global GHG emissions (Steinfeld et al., 2006). 

Water Shortage and Pollution

Water is essential for life. Only 3% of the water on Earth is fresh, and surface water only accounts for 0.3% of the total amount of freshwater (this includes lakes, rivers, and streams). Another 68.7% of all freshwater is locked away in glaciers, while 30% of freshwater is located within the pores of the ground in the form of groundwater (US EPA, 2013). Approximately 64% of the world's population is expected to live in water-stressed basins by 2025 (Steinfeld et al., 2006).

Water shortage in China (photo from The Guardian)

Freshwater is extensively used in livestock agriculture, the most significant use coming from the irrigation of crops for intensive feeding operations. The livestock sector is a key player in increasing water use and represents 8% of global human water use (Steinfeld et al., 2006). For instance, approximately 16,000L of water are needed to produce 1kg of beef (Janzen, 2011). In terms of water pollution, the major sources from the livestock sector include animal waste, antibiotics and hormones, chemicals from tanneries, fertilisers and pesticides for feedcrops, and sediments from eroded pastures. These pollutants contribute to freshwater eutrophication, coastal dead zones, and the degradation of coral reefs, among others (Steinfeld et al., 2006).

As I mentioned above, these are only some of the many environmental impacts of livestock agriculture. Livestock's Long Shadow by Steinfeld et al. is currently the most comprehensive study on the environmental impacts of the livestock sector. I strongly recommend flipping through it if you're eager to learn more on the topic.

Having read about some of the environmental impacts arising from the livestock sector, what do you think are potential solutions for a more sustainable food industry? 

Thanks for reading!

Food Waste Follow-Up, and a Recipe

Before going on to explore some of the modern environmental impacts of global food production, here's an update on my October post about food waste in the news.

What's been going on since then? A report was released by WRAP in November which builds upon their previous research. The results for 2012 were quite interesting: the amount of food waste decreased by 21% between 2007 and 2012, but 4.2 million tonnes of food were still wasted during the year (approximately equal to £12.5 billion). In terms of environmental impacts, avoidable food waste from the UK was associated with approximately 17 million tonnes of CO2 equivalent. In addition, estimates of the amount of land required to produce the food that is wasted were created for the first time. The total land area was found to be approximately 91% of the size of Wales.

Globally, food waste accounts for more greenhouse gas emissions than any country, with the exception of the US and China. In a recent report, the U.N. Food and Agriculture Organisation (FAO) created figures on the carbon footprint associated with food waste which were estimated at 3.3 billion tonnes of CO2 per year. These results are quite distressing and underline the urgent need for a global strategy for a sustainable food system. In their recent study, Godfray et al. (2010) discuss possible solutions for sustainable agricultural intensification, but identify that there is no clear-cut solution. With growing global populations, the issue of food waste is one that will not quickly disappear.

In other food waste related news, The Ecologist recently wrote a piece about the Pig Idea in their article titled Let them eat waste! In November, a knees-up was hosted in Trafalgar Square by the organisation where eight pigs fed entirely on food waste were devoured. The Pig Idea endeavours to get the feeding of food waste to livestock back on the table to avoid unnecessarily growing animal feed. According to studies by Myer et al. (1999) and Westendorf et al. (1998), food waste has nutritional value and could be used in swine diets without compromising the quality and flavour of the meat. What are your thoughts on feeding food waste to livestock? 

Does all this make you eager to take action on food waste in your daily life? Check if your council provides food waste recycling services - Camden, for instance, provides an excellent food recycling service. Here's an informative little video on two different ways food waste can be recycled, namely in-vessel composting and anaerobic digestion. For more information on the effectiveness of these two methods of composting, see Kim et al. (2008) and Righi et al. (2013) respectively.

Aside from composting, there are other things you can do to improve your waste footprint. Not sure what to do with the vegetables in the bottom of your fridge that are almost at the end of their lives? An excellent way to use up old vegetables is to make a pot of soup - aside from reducing food waste, soups are very healthy, cheap and easy to make, and last a long time. To conclude this post, I'd like to share with you one of my favourite lentil soup recipes from a local restaurant called The Green Door in my hometown of Ottawa.

Thanks for reading!

Green Lentil Soup 

Recipe from the Green Door Vegetarian Cookbook

Ingredients:

1c green lentils
4c water
2 tbsp olive oil
1 diced onion
2 stalks diced celery
1 diced carrot
8c water or stock
1 clove garlic
3 bay leaves
1 tsp salt
1/2c chopped parsley

1. Wash and drain lentils, and place in pot. Add 4 cups water and bring to a boil. Lower heat and cook for 5 minutes, then drain.

2. In a soup pot, heat oil, saute onion, carrot, and celery until soft. 

3. Add water or stock and bring to a boil. 

4. Add lentils, garlic, bay leaves and salt (if using). 

5. Cook for 20 minutes or until lentils are well cooked. Adjust seasoning if necessary.

6. Serve topped with parsley, and enjoy!